<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.7.14/dist/vue.js"></script>
</head>

<body>
    <div id="app">
        <p>请选择你要购买的书籍</p>
        <ul>
            <li v-for="item in arr"> {{item.name}} <button @click="item.count++">买书</button></li>
        </ul>
        <table border="1" width="500" cellspacing="0">
            <tr>
                <th>序号</th>
                <th>书名</th>
                <th>单价</th>
                <th>数量</th>
                <th>合计</th>
            </tr>
            <tr v-for="(item,index) in arr">
                <td>{{index}}</td>
                <td>{{item.name}}</td>
                <td>{{item.price}}</td>
                <td>{{item.count}}</td>
                <td>{{item.price*item.count}}</td>
            </tr>
        </table>
        <p>总价格为:{{totalPrice}} </p>
    </div>
    <script>
        const app = new Vue({
            el: '#app',
            data: {
                arr: [{
                    name: "水浒传",
                    price: 107,
                    count: 0,
                }, {
                    name: "西游记",
                    price: 192,
                    count: 0,
                }, {
                    name: "三国演义",
                    price: 219,
                    count: 0,
                }, {
                    name: "红楼梦",
                    price: 178,
                    count: 0,
                }, ]
            },
            computed: {
                totalPrice() {
                    return this.arr.reduce((sum, item) => sum + item.price * item.count, 0)
                }
            }
        })
    </script>
</body>

</html>